Interactive television services have been developed since the digital television service has been available. In addition to the ordinary digital television service, interactive services have problems that relate to data communications and incompatibility. Traditionally, television sets have been able to receive broadcast transmissions. In order to provide interactive services in association with a moving picture transmission or delivery service, a receiver unit of the service consumer, such as a television set, a set-top box or a computer, must also be able to transmit information back to server computers and other similar apparatuses provisioned by service provider of the moving picture transmission or delivery service provider or a party affiliated with the service provider. The transmission of information back to the service provider is catered for with a back-channel or, in other words, a reverse-channel, which may be an Internet connection over a Digital Subscriber Line (DSL) such as ADSL, an Integrated Services Digital Network (ISDN) connection or a modem connection. The connection may also be by a bi-directional cable television providing an Internet service in association with cable television service. The back-channel or the reverse channel must provide for an Internet Protocol (IP) network connectivity to the server computers of the service provider. The server computer may be provided with sufficient knowledge on the content of the moving picture to be able to associate request messages received via the back-channel with a particular service request.
The most common interactive services include interactive program guide, web browsing, video on demand, chat services and other similar services. The services can be implemented so that they are available at the same time as the ordinary broadcast service or equivalent scheduled moving picture content delivery service. For example, it is possible to watch a football game and share comments with a friend on a chat screen that is located in a separate area on the screen.
A modern television set comprises a digital receiver. Most advanced digital receivers are able to provide the services mentioned above and even more, as they are capable of executing software products in a processor and memory associated with the digital receiver. The receivers may include a mass storage device such as a hard disk drive for storing television programs or computer software to be executed. When the receiver is started, it loads the software needed for the services mentioned above, such as the chat screen application mentioned above.
The problem of the known applications is that they are very limited. Limitations are caused by incompatibility and limited data transfer capabilities. Thus, there is a need for a mechanism for providing advanced interactive functions in a television.